Ice drill with adjustable cutting edges

ABSTRACT

An ice drill mounts a pair of cutters on a pair of sockets rotatably supported on a bar connected transversely to the end of a drill shaft. The angular orientation of the sockets, and hence the cutters, on the bar may be adjusted by rotating an adjustment member which engages a notch on each socket. Rotation of the adjustment member causes rotation of the sockets in opposite directions but with equal angular displacement thereby maintaining equal cutting angles for the two cutters.

United States Patent Jonsson et al.

[ 1 Mar. 19, I974 ICE DRILL WITH ADJUSTABLE CUTTING EDGES [75] Inventors: Arvid Jonsson; Jonas Erland Jonsson; Per August Malmen, all of Malung, Sweden [73] Assignee: AB Arjon, Malung, Sweden [22] Filed: Apr. 25, 1972 [21] Appl. No.: 247,366

[30] Foreign Application Priority Data Apr. 28. 1971 Sweden 5482/71 [52] U.S. Cl. 175/18, 175/382 [58] Field of Search 175/381-384, 175/18, 394, 272, 279,286

[56] References Cited UNITED STATES PATENTS 3.397.750 8/1968 Wicklund 175/18 310,608 l/1885 Osborn 175/382 3,131,777 5/1964 Snider t. 175/18 3,342,276 9/1967 Beck 175/286 Primary Examiner-Henry C. Sutherland Assistant Examiner-Richard E. Favreau Attorney, Agent, or Firm-Brumbaugh, Graves, Donohue & Raymond [57] ABSTRACT 13 Claims, 7 Drawing Figures PATENTED 1 9 3. 797, 588

SHEET 2 [IF 2 1 ICE DRILL WITH ADJUSTABLE CUTTING EDGES BACKGROUND OF THE INVENTION This invention relates to cutting drills, and more particularly to an ice drill having adjustable cutting edges.

The use of ice drills having fixed cutting edges has not proven satisfactory in use for drilling lake ice because the consistency of lake ice is not constant, but varies as a function of the weather conditions and the chemical and mineral content of the water. Seasonal weather changes have the greatest effect on the ice consistency, causing changes of state from hard, dry, homogenous, black ice in the autumn to wet, course granulated ice in the spring, and with intermediate degrees of hardness, wetness and homogenity in the intervening periods. Therefore, it is necessary for an ice drill useable on lake ice to have adjustable cutting edges to accommodate the different states of the ice.

In attempting to fill this need, ice drills having exchangeable cutting edges have been manufactured. In addition, ice drills are available whose cutting angles are incrementally adjustable by loosening the screws securing the cutting edges to the drill and inserting spacers. However, this must be done by hand individually for each cutting edge, which is troublesome and does not give an accurate, continuously variable adjustment of the cutting angle.

SUMMARY OF THE INVENTION The present invention overcomes these difficulties by providing an ice drill suitable for all types of ice, having exchangeable cutting edges which are continuously adjustable by means of a simple movement of the hand. This adjustment is achieved by mounting the cutting edges on a pair of sockets rotatably mounted on a transverse bar. The angular position of the sockets on the transverse bar is continuously adjustable by means of an adjustment member which engages the sockets and rotates them in equal and opposite angular displacements to maintain equal cutting angles for both cutting edges.

DESCRIPTION OF THE DRAWINGS This invention will be-described in the form of examples with reference to the drawings in which:

FIG. 1 is a cross-sectional elevation of the lower part of an ice drill of the helical type;

FIG. 2 shows a partial view of a detail of the drill shown in FIG. 1;

FIG. 3 shows a further detail of the drill shown in FIG. 1;

FIG. 4 is a cross-sectional elevation of the lower part of another embodiment of an ice drill of the helical yp FIG; 5 is a plan view of the end of the lower part of the drill shown in FIG. 4;

FIG. 6 is a cross-section of a detail of the ice drill shown in FIG. 4; and

FIG. 7 shows a view in detail of the ice drill shown in FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT The ice drill according to FIGS. 1, 2 and 3 includes a drilled shaft 1 to which a helix (not shown) is attached to remove drill ice. At the lower part of the drill shaft 1 a cylindrical cutter support bar 2 is connected e.g., by welding. The bar 2 extends transversely to the drill shaft and is bent somewhat upwards, as evident from the drawing, in order to obtain the desired nose angle for a pair of cutting edges 3. Each blade 3 has a cutting edge defined by the intersection of the planes defining the top surface of the blade and the bottom surface of the blade. The blades 3 are attached to a pair of sockets 4 either permanently, as by welding directly to the socket (as in FIG. 7) or detachably, as by means of screws 5 to a supporting plate 6 attached to the socket, as illustrated in FIG. 2. Each socket 4 is rotatably mounted on the bar 2 and is provided with a recess 7 at the end facing the drill shaft 1. Each socket 4 is also provided with an arm 8 having a laterally extending hole 9 for receiving a lock bolt 10 which goes through the drill shaft 1 and may be tightened to lock the sockets 4 at any desired setting. The arm 8 is attached to the socket 4 intermediate the ends of the socket so that an interspace is formed between the drill shaft 1 and the arm 8. An adjusting collar 11, rotatably disposed around the drill shaft 1 in the interspace, is provided with downwardly extending studs 12, which engage the recesses 7 of the sockets 4.

When the lock bolt 10 is loosened, rotation of the adjusting collar 11 will rotate the sockets continuously and uniformly, but in opposite directions. Thus, the blades 3 will be inclined more or less and the cutting angle of each blade, defined as the angle, at the cutting line, between the plane defining the lower surface of the blade 3, and the surface of revolution of the cutting edge about the axis of the drill shaft, will be altered equally. When the desired cutting angle has been reached, the lock bolt 10 is retightened to lock the arms 8 and the sockets 4 against further rotation around the bar 2.

As is evident from FIG. 1, the sockets are secured against outward axial movement by means of plates 13 and screws 14. These screws may be tightened against the outside axial face of the sockets to provide an additional locking function thereon in order to further and more securely fix the blades in the adjusted position. When the lock bolt 10 and the screws 14 and their plates 13 are removed, the sockets 4 and their blades 3 may easily be removed in order to replace them.

In FIGS. 4 through 7, another embodiment of the invention is shown. Those parts in FIGS. 4-7 which are identical or similar to corresponding parts in FIGS. 1 through 3 have been assigned the same or primed reference numerals.

Two rotatable sockets 4 provided with blades 3, are mounted, each on the bar 2 attached to the drill shaft 1. As in the embodiment of FIGS. 1 through 3 the blades 3 may be attached to the sockets either directly and permanently by welding or detachably by screwing thereto via a supporting plate 6. The sockets 4' are each provided with a recess 7' formed in its axial end adjacent the drill shaft. An adjusting arm 15 is rotatably mounted on a stud l6 protruding from the drill shaft 1. The adjusting arm 15 is provided with an oblong hole 17 through which a screw 17' extends to threadedly engage the shaft for releasably locking the adjusting arm arm 15 against rotation. Two studs 18 extend from the plane of the arm 15, as most clearly shown in FIG. 6, and engage the recesses 7' in the sockets 4'. By rotating the adjusting arm 15 around the stud 16, the sockets 4' with their blades 3 will be rotated in equal and opposite directions in relation to each other and with an angular displacement that is a function of the degree of rotation of the adjusting arm 15. It is thus possible to adjust the cutting angles of the blades 3 continuously and synchronously.

A helix, schematically suggested at 19, is attached to the drill shaft 1. The sockets 4', as in the previously described embodiment, are locked axially by means of plates 20 and screws 14, and to supplement the locking function of screw 17' on the sockets, they may be further secured against rotational slipping by the plate 20 and the screw 14 to lock the blades 3 at the desired cutting angle. One of the plates 20 may, as indicated in FIG. 5, provide a supporting connection between the cutter support bar 2 and the outer edge of the lower part of the helix 19. This is obtained by providing the plate 20 with an ear 22, which is fixed to the lower part of the helix by means of a pin or the like. By means of this design of the plate 20 it is possible to replace the blade and the socket in a simple way but still obtain a rigid attachment to the helix. The screw 14 is screwed out and the plate 20 is turned aside, whereby the socket 4 may be withdrawn from the bar 2. This design of the plate 20 may also be used in the embodiment according to FIGS. 1 through 3.

As evident from the above description, the present invention provides an ice drill in which the cutting angle of the blades may be adjusted synchronously and continuously by a simple movement of the hand. The drill according to this invention may be adjusted optimally for the condition of the ice in which one wants to drill as well as the power resources of the user. The blades are simple to exchange when they are worn out or for any other reason.

The invention is not limited to the embodiments described. For example, it is possible to utilize the helix as an adjusting means by arranging the helix rotatably around the drill shaft and attaching the blades directly to a rotatable and lockable carrier formed of angle bars connected to the drill shaft. The cutting angle is thus adjustable by shifting the angular position of the helix with respect to the shaft. The invention may also be utilized in other types of ice drills. As evident from FIG. 4 the adjusting arm 15 may be provided with an index or any type of a graduation, whereby it is possible to recommend certain values or a certain adjustment depending on the type of ice. In the embodiment of FIGS. 1 through 3, the graduation may be arranged on the arm 8. It is thus to be expressly understood that the invention may be practiced otherwise than as described herein while remaining within the spirit and scope of the appended claims.

We claim:

1. In an ice drill having a drill shaft and two cutting blades, said cutting blades each having a cutting edge and a cutting angle defined as the angle between the plane defining the lower surface of the cutting blade and the surface of revolution of said cutting edge about the axis of said drill shaft, wherein the improvement comprises means for adjustably mounting said cutting blades tosaid ice drill, including:

socket means to which said cutting blades are secured with the cutting edge thereof generally parallel to the axis of said socket means;

means for rotatably mounting said socket means on an axis substantially transverse to said drill shaft;

adjusting means for adjusting said socket means to cause said blades secured to said socket means to move uniformly and simultaneously in opposite directions to each other; and

engaging means on said socket means by which said adjusting means engages said socket means.

2. An ice drill according to claim 1, characterized in that the adjusting means is a rotatable collar arranged coaxially to the drill shaft.

3. An ice drill according to claim 1, characterized in that adjusting means is an arm which is mounted to the drill shaft and is swingable in a plane substantially parallel to the longitudinal axis of the drill shaft.

4. An ice drill according to claim 1, characterized in that said adjusting means includes studs and said engaging means includes means defining recesses receiving and engaging said studs.

5. An ice drill according to claim 1, characterized in that the adjusting means is provided with means for locking said adjusting means in relation to the drill shaft.

6. An ice dn'll according to claim 1 wherein said rotatably mounting means comprises a bar mounted on said drill shaft extending transversely thereto on which said socket means are rotatably mounted.

7. An ice drill according to claim 6, characterized in that said engaging means includes means defining recesses in said socket means.

8. An ice drill according to claim 6, characterized in that the socket means are provided with arms which are adjustable with respect to the drill shaft, and lockable thereto, by means of a screw device.

9. An ice drill according to claim 6, characterized in that the socket means are prevented from sliding off said bar by means of a screw which is threadably engaged in said bar, and which, when tightened down against a plate, presses the socket means to be locked inward towards the drill shaft.

10. An ice drill according to claim 9 further comprising a helix, characterized in that the plate is swingably mounted to the outer edge of the lower end of the helix.

11. An ice drill, comprising a drill shaft and two adjustable blades, characterized in that the blades are linked to the drill shaft through socket means which are rotatably adjustable to provide an adjustable cutting angle, and which are provided with engaging means arranged symmetrically in relation to said blades and to the drill shaft, said engaging means engaging an adjusting means including a rotatable collar disposed coaxially around the drill shaft and arranged to cause the socket means and thus the blades to move uniformly and simultaneously in opposite directions to each other.

12. An ice drill, comprising a drill shaft and two adjustable blades characterized in that the blades are linked to the drill shaft through socket means which are rotatably adjustable to provide an adjustable cutting angle, and which are provided with engaging means arranged symmetrically in relation to said blades and to the drill shaft, said engaging means engaging an adjusting means including an arm which is mounted to the drill shaft and is swingable in a plane substantially parallel to the longitudinal axis of the drill shaft, said adjusting means arranged to cause the socket means and thus the blades to move uniformly and simultaneously in opposite directions to each other.

socket means being further provided with engaging means arranged symmetrically in relation to said blades and to said drill shaft, said engaging means engaging an adjusting means arranged to cause said socket means and blades to move uniformly and simultaneously in opposite directions to each other. 

1. In an ice drill having a drill shaft and two cutting blades, said cutting blades each having a cutting edge and a cutting angle defined as the angle between the plane defining the lower surface of the cutting blade and the surface of revolution of said cutting edge about the axis of said drill shaft, wherein the improvement comprises means for adjustably mounting said cutting blades to said ice drill, including: socket means to which said cutting blades are secured with the cutting edge thereof generally parallel to the axis of said socket means; means for rotatably mounting said socket means on an axis substantially transverse to said drill shaft; adjusting means for adjusting said socket means to cause said blades secured to said socket means to move uniformly and simultaneously in opposite directions to each other; and engaging means on said socket means by which said adjusting means engages said socket means.
 2. An ice drill according to claim 1, characterized in that the adjusting means is a rotatable collar arranged coaxially to the drill shaft.
 3. An ice drill according to claim 1, characterized in that adjusting means is an arm which is mounted to the drill shaft and is swingable in a plane substantially parallel to the longitudinal axis of the drill shaft.
 4. An ice drill according to claim 1, characterized in that said adjusting means includes studs and said engaging means includes means defining recesses receiving and engaging said studs.
 5. An ice drill according to claim 1, characterized in that the adjusting means is provided with means for locking said adjusting Means in relation to the drill shaft.
 6. An ice drill according to claim 1 wherein said rotatably mounting means comprises a bar mounted on said drill shaft extending transversely thereto on which said socket means are rotatably mounted.
 7. An ice drill according to claim 6, characterized in that said engaging means includes means defining recesses in said socket means.
 8. An ice drill according to claim 6, characterized in that the socket means are provided with arms which are adjustable with respect to the drill shaft, and lockable thereto, by means of a screw device.
 9. An ice drill according to claim 6, characterized in that the socket means are prevented from sliding off said bar by means of a screw which is threadably engaged in said bar, and which, when tightened down against a plate, presses the socket means to be locked inward towards the drill shaft.
 10. An ice drill according to claim 9 further comprising a helix, characterized in that the plate is swingably mounted to the outer edge of the lower end of the helix.
 11. An ice drill, comprising a drill shaft and two adjustable blades, characterized in that the blades are linked to the drill shaft through socket means which are rotatably adjustable to provide an adjustable cutting angle, and which are provided with engaging means arranged symmetrically in relation to said blades and to the drill shaft, said engaging means engaging an adjusting means including a rotatable collar disposed coaxially around the drill shaft and arranged to cause the socket means and thus the blades to move uniformly and simultaneously in opposite directions to each other.
 12. An ice drill, comprising a drill shaft and two adjustable blades characterized in that the blades are linked to the drill shaft through socket means which are rotatably adjustable to provide an adjustable cutting angle, and which are provided with engaging means arranged symmetrically in relation to said blades and to the drill shaft, said engaging means engaging an adjusting means including an arm which is mounted to the drill shaft and is swingable in a plane substantially parallel to the longitudinal axis of the drill shaft, said adjusting means arranged to cause the socket means and thus the blades to move uniformly and simultaneously in opposite directions to each other.
 13. An ice drill, comprising a drill shaft and two adjustable blades, characterized in that the blades are linked to the drill shaft through socket means which are rotatably adjustable to provide an adjustable cutting angle, said socket means being provided with arms which are adjustable with respect to the drill shaft and lockable thereto by means of a screw device, said socket means being further provided with engaging means arranged symmetrically in relation to said blades and to said drill shaft, said engaging means engaging an adjusting means arranged to cause said socket means and blades to move uniformly and simultaneously in opposite directions to each other. 